Joint



May 3, 1938- G. H. HUFFERD ET AL 2,115,774

JOINT Filed Nov. 23. 1934 fg 1., Egg/ Z I jf j! 22 M IZ 16 E I/Ez-Ebarge ff. uf/wd.

Patented May 3, 1938 JOINT George nimmer-d ma Matthew P. Graham, De-

troit, Mich., asslgnors to Thompson Products Incorporated, Cleveland,Ohio, a corporation of Ohio Application November 23,1934, serai No.154,424

1 claim. (ci. zarsai This invention relates to joint constructionshaving bearing surfaces alternating with nonbearing portions forpermitting full bearing engagement irrespective of the wearing away ofthe 5 bearing surfaces.

More specifically, this invention relates to joints suitable for use indrag links and tie rod connections and having studs extending therefromin bearing relation with the joint housing on at least two separatebearing surfaces in the housing in spaced relation, said bearingsurfaces being disposed in a direction encountering the most movementduring use of the joint.

Tie rod joints have heretofore been provided with compensating means totake up for wear of the bearing surfaces in order that the stud elementof the joint might be maintained in full bearing contact with thebearing surfaces of the housing. However, these bearing surfaces alwaysextended entirely around the inside periphery of the housing. Usuallythe stud element is attempted to be urged into f ull seating cooperationwith the circumferential bearing surfaces of the housing by means of aspring member or other resilient device. l

However, the studs of tie rod joints are subjected to tilting action inone plane more than in other planes, so that those portions of thebearing surface ofthe housing permitting tilting in this plane wear awaymore rapidly than do those portions ofthe bearing surfaces which are notsubjected to sc much'movement. As a result, -the bearing portionssubjected to less wear are not worn down evenly .with the othervportions 35 during use of the joint, and the stud element cannot beurged into full seating engagement with the worn away portion because ofthese unworn portions. Consequently, the stud element soon becomesloosened in the joint housing and 40 rattles because the Aspring membercannot urge the element into full seating engagement with the housingbearing surface. 'Ihis diiliculty is especially encountered in tie rodconstructions for independently sprung front wheels of auto- .5 mobilevehicles, wherein the free vertical movement of the wheels causes anincreased tilting of the tie rod joint studs in one plane, whereastilting in other planes is not increased. This increased tiltingmovement is in a plane containing 50 the .axis of the tie rod, or aplane parallel thereto.

We have now provided a tie rod construction.

wherein the bearing surfaces of the housing are cut away except wherethe main bearing contact 'due to this increased tilting movement takes55 place. With this arrangement the stud may freely tilt in anydirection relative to. the tie rod and at the same time the stud can beurged into full circumferential contact with the localized bearingsurfaces of the housing irrespective of the wear of said bearingsurfaces.

It is therefore an object of this invention to provide a jointconstruction having localized bearing surfaces so arranged as to be infull circumferential contact with the stud element irrespective of theamount of wear of said surfaces dur- 10 ing use of the joint;

A further )object of this invention is to provide a joint structurehaving a stud element freely rotatable and tiltable with `respect to ahousing member and capable of being maintained in full '15circumferential contact with discontinuous bearing surfaces of saidhousing member irrespective ofthe amount of wear encountered during useof the joint..

It is a further object of this invention to provide a joint housing witha pair of spaced bearing surfaces positioned where the bearing load isgreatest.

A specific object of this invention is to provide a joint structure witha freely rotatable and tiltable stud element extending from a housingmember and with the bearing surfaces of said housing member so arrangedand localized that the stud can be urged into full annular contacttherewith irrespective of the amount of wear of said sur- 30 faces.

-Other and further objects of this invention will be apparent from thefollowing description and annexed sheet of drawings which forms a part'of this specification:

On the drawing:

Figure l is a central cross-sectional view of a joint housing havingpairs of bearing surfaces' therein according tothis invention, andillustrating the stud element in elevation. 40

Figure 2 is a cross-sectional view taken substantially along the; lineII`II of Figure l with parts in elevation. V

Figure 3 is a. bottom plan view of the joint housing shown in Figures 1and 2. 45

Figure 4 is a central cross-sectional view of an alternative form ofjoint housing according to this invention *with a stud element extending`therethrough shown in elevation.

Figure 5is a cross-sectional view taken substantially along the line V-Vof Figure 4 with parts in elevation.

Figure 6 is a central cross-sectional view of another form of jointhousing according 'to this 55 invention, showing the stud elementextending therethrough in elevation.

Figure 7 is a cross-sectional view taken substantially along the lineVII-VII of Figure 6 with parts in elevation.

As shown on the drawing: In Figures 1, 2 and 3 the reference numeral I l`indicates generally a joint housing having a stud element extendingtherefrom in freely rotatable and tiltable relation therewith. The studelement II is provided near the end thereof with a segmental sphericalbearing surface I2 and a heini-spherical ball end I3.. The joint housingdefines an enlarged cylindrical chamber I4 extending through the bottomof the housing. and a smaller cylindrical chamber I5 through which thestud element extends from the housing. A pair of spaced frusto-conicalbearing surfaces I6 and I1 are disposed at opposite sides of the joint,housing and have out away non-bearing portions I8 and I9 (Figure 3)therebetween. As shown in Figure 3, the bearing surfaces I6 and' I1 areon opposite sides of a plane normal to a plane containing the axis ofthe shank portion 20 which extends laterally from the housing Il intothreaded engagement with the end of a tie rod 2I (Figure 2). The shank23 is held in proper threaded position in 'the tie rod end 2I by meansof a clamp 22.

A dished member 23 having side walls 24 for engagement with the sidewalls of the housing I0 and a depressed center portion 25 is inserted inthe chamber I4 of the housing. A helical coiled spring 26 is placed inthe dished cap 23 and is held therein under compression by means of aclosure plate 21 which is secured in place by peening over the metal ofthe joint housing, as shown at 23. The depressed portion 25 of the capmember 23 is adapted to receive the ball end I3 of the stud element II.The spring 26 urges the cap member into engagement with the ball end andforces the bearing portion I2 of the stud element II into proper seatingrelation with the bearing surfaces IB and I1 of the housing.

The segmental spherical bearing portion I2 of the stud II makes a linecontact with the frusto conical bearing surfaces I6 and I1. of thehousing, and as these bearing surfaces wear away during use of thejoint, the stud member is forced upwardly to continuously reseat itself.Since most of the tilting action, as pointed out above, is in a planecontaining the axis of the tie rod, the bearing surfaces are so disposedin the joint housing as to fully provide for the wearing action. 'I'henon-bearing portions I8 and I3 do not Dcontact the stud bearing portionI2 and thus cannot prevent the stud from reseating itself as the bearingsurfaces I6 and I1 wear away. It is obvious that if the bearing surfacesI6 and I1 were exltended circumferentially around the joint housing,those portions not subjected to wear would prevent the stud from moving`upwardly in the housing and eventually the stud bearing portion I2 wouldbe actually 'spaced from those portions of the bearing surfaces whichare subjected to the most wear. f

In Figures 4 and 5,` another form of joint construction embodying theprinciples of this invention is shown. Identical parts have been Imarkedwith thesame reference numerals used in Figures 1 to 3 inclusive. '-Inthe modification shown ,,in Figures 4 and 5, however, the bearingsurfacesof -the housing I Il are not formed integral with the housing,but are formed on an annular member 3l in tight frictional engagement inthe cavity I4 of the housing with the side walls thereof. The

top of the housing is provided with an inturned annular flange 3|. IIheseating member 30 is forced into the housing from the bottom thereof andabuts the iiange 3|. The insert may be placed in the housing by a diepress or, by heating the housing and allowing the same to contractaround the insert so that it is maintained in fixed position in thechamber I4.

'I'he member 3l is provided with two spaced segmental spherical bearingportions 32 and 33 similar to the frusta-conical bearing portions I6 andI1 shown in Figures 1 to 3. The segmiental spherical bearing portions 32and 33 alternate with cut away non-bearing portions 34 'and 35. Thesegmental spherical bearing portion I2 of the stud member II is forcedinto full bearing contact with these localized segmental sphericalbearing portions 32 and 33 instead of into a line contact asshown inFigures 1 and 2 where the housing bearing surfaces are conical in shape.Thelocalized bearing surfaces 32 and 33 are on opposite sides of a planenormal to a plane containing the axis of the tie rod while thenonbearing portions 34 and 35 are on opposite sides of a vertical planecontaining the axis of the tie rod since the tilting action of the studmember II is more pronounced in the vertical plane containing the axisof the tie rod.

The closure plate member for the joint housing I0, as shown in Figures 4and 5, comprises a fiat plate 36 having an inturned flange 31 definingan opening through which lubricant may be inserted. A plug (not shown)may be force tted into this opening or maybe in screw thread relationwith the opening. The dished cap member 23 may be provided with holes39, as shown in Figures 4 and 5, so that lubricant inserted through theopening in the closure plate 36 can pass through the cap 23 tolubricatethe bearing surfaces of the joint.

In Figures 6 and 7, another form of joint con struction is illustratedembodying the principles of this invention. Identical parts have beenmarked with the same reference numerals used in Figures 1 to 5inclusive.

As shown in Figures 6 and 7, the segmental spherical bearing portion I2of the stud II is circumscribed by a henri-spherical seating member 40having an outside segmental spherical bearing surface 4I and an insidesegmental spherical bearing surface 42. The seating member 40 is alsoprovided with a. cylindrical bearing surface 43 defining a circularopening through which the stud II projects. A bearing surface 44 isformed on the stud I I for engagement with the cylindrical surface 43 ofthe seating element.

The joint housing has formed therein a pair of localized segmentalspherical bearing surfaces 45 and 46, alternating with a pair ofnon-bearing portions 41 and 43. The seating member 40 may be coined by asimple stamping operation and the stud element II is urged into seatingengagement with the spherical bearing portion I2 of the stud element isin bearing engagement with the inside bearing surface 42 of the seatingmember 40.

Since the outer bearing surface 4| of the seating element 40 is inbearing engagement with the pair of localized segmental sphericalbearing surfaces 45 and 4 of the housing III and is spaced from theportions 41 and 48, the seating member on the stud can be urged intofull bearing engagement with these localized housing bearing surfacesirrespective of the amount of wear encountered. If the bearing surface45 or 46 were extended entirely around the housing wall, a wearing ofoppositely disposed portions of this housing would occur at the pointsubjected to the most movement. The other oppositely disposed portionswould not `wear away as much and would prevent the stud element frombeing forced into full bearing engagement with the wom-away portions. Asa result, the seating element would be loosened at these points and thejoint structure would rattle and eventually be unfit for use. As pointedout above the stud is tilted most in a vertical plane containing theaxis of the tie rod and those portions of the housing bearingsurcontaining the axis of the tie rod are subjected to most wear. Thoseportions oi' the housing bearing surfaces on opposite sides of thevertical plane containing the axis of the tie rod, are subjected tolittle or no wear. Therefore, these last named bearing portions are nowdiskpensed with according to this invention so that they will notprevent an automatic adjustment of the stud element to compensate forwear of the housing bearing surfaces.

Each localized bearing surface preferably extends around about onefourth of the circumference of the housing. In other words, thisinvention provides for the cutting away of two opposite one fourthsections of the full circumferential housing bearing surface usedheretofore.

It should be understood that this invention is applicable to any form ofjoint construction embodying the principles of the constructionsillustrated in Figures 1 to 7. Thus the bearing surfaces of the housingmay be formed integral with the housing as shown in Figures 1, 2, 3, 6and 'l or may be inserted as a separate element into the housing asshown in Figures 4 and 5. The bearing surfaces themselves may befrusto-conical in shape, as shown in Figures 1 to 3, or segmentalspherical in shape as shown in Figures 4 to 7. The bearing surface ofthe stud may directly en- .v gage the bearing surface of the housing asshown in Figures 1 to 5, or a seating member may be interposed betweenthe stud member and the joint housing as shown in Figures 6 and 7. Theprinciple of this invention can also be embodied in other forms of jointstructures.

Having now described our invention, we claim as our invention:

In a joint including a housing having an inner bearing wall, a studhaving an end inbearing relation to said wall for swivelling and tiltingmovement of said stud with respect to said housing, and means constantlyurging said end and wall into closer bearing relation, said wall beingarranged for bearing contact with said stud over the localized areaswithin which most of said tilting movement takes place and beingrelieved between said areas, whereby said means is at all timeseffective to urge said end and wall into reseating bearing relation tocompensate for continued wear within said localized areas.

-1 i GEORGE H.- HUFFERD.

MA-'rrmxw P. GRAHAM.

